Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Net Investment Income [Line Items]
Gross investment income	$ 1,338	$ 1,362	$ 2,689	$ 2,671
Less: Investment expenses	80	86	162	172
Net investment income	1,258	1,276	2,527	2,499
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	913	928	1,827	1,836
Trading securities (1)
Net Investment Income [Line Items]
Gross investment income	(1)	0	10	0
Equity securities
Net Investment Income [Line Items]
Gross investment income	1	0	1	2
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	255	250	511	495
Policy loans
Net Investment Income [Line Items]
Gross investment income	14	14	25	23
Limited partnerships and LLCs
Net Investment Income [Line Items]
Gross investment income	80	98	151	172
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross investment income	53	47	114	94
Other
Net Investment Income [Line Items]
Gross investment income	$ 23	$ 25	$ 50	$ 49

Amount, before investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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